Content streaming, such as the streaming of audio, video, and/or text is becoming increasingly popular. The term “streaming” is typically used to indicate that the data representing the content is provided over a network to a client computer on an as-needed basis rather than being pre-delivered in its entirety before playback. Thus, the client computer renders streaming content as it is received from a network server, rather than waiting for an entire “file” to be delivered.
The widespread availability of streaming multimedia content enables a variety of informational content that was not previously available over the Internet or other computer networks. Live content is one significant example of such content. Using streaming multimedia, audio, video, or audio/visual coverage of noteworthy events can be broadcast over the Internet as the events unfold. Similarly, television and radio stations can transmit their live content over the Internet.
The Session Description Protocol (SDP), Network Working Group Request for Comments (RFC) 2327, is a text-based format used to describe properties of a multimedia presentation, referred to as a “session”, and properties of one or more media streams contained within the presentation. SDP has been developed as an application level protocol intended for describing multimedia sessions for the purposes of session announcement, session invitation, and other forms of multimedia session initiation. SDP can be used in accordance with other protocols, such as the Real-Time Streaming Protocol (RTSP) or the HyperText Transfer Protocol (HTTP), to describe and/or negotiate properties of a multimedia session used for delivery of streaming data.
However, in many situations it is difficult to get the SDP information from the network server to the client computer. For example, the network server may be streaming a series of multimedia presentations to the client computer, such as presentations listed in a play list. When the network server switches from streaming one presentation to the next, it is oftentimes difficult for the SDP information for the next presentation to be made available to the client computer. Thus, it would be beneficial to have an additional mechanism by which the SDP information can be made available to the client computer.